(1) Field of the Invention
The invention relates to the reduction of a visible wake of a surface vessel or underwater vessel having a structure extending above the surface, and of a submerged wake.
(2) Description of the Prior Art
The surface wake of a ship, or a near surface submarine, is easy to detect from an airplane or satellites. The underwater wake of a propulsor can last for long distances because it is basically a longitudinal vortex, which dissipates slowly. A device to control such wakes would provide stealth to such vessels when needed. In commercial applications, the mitigation of a wake of a large vehicle or propulsor allows closer spacing of ships moving in line one behind the other.
There is a need for devices for mitigating as well as detecting propulsor wakes, for both underwater and surface vehicles. Wake mitigation makes the acoustic and non-acoustic diagnostic of the wakes of vehicles more difficult. For surface ships, any mitigation of the frothy white wakes of vehicles makes their direct visual or satellite observation somewhat more difficult.